I have a setup with a PRI and Sangoma card. It looks like the Sangoma has failed. The provider can give us generic SIP to go around the Sangoma. The router is now a device on the local network. I was able to setup the SIP connection but the call terminates at about 15 secs. The provider tells me 3cx is looking for a registration acknowledgement. There should be no registration. I think 3cx is terminating the call because it's not getting registration confirmation. How can I stop 3cx from requiring registration?